Bibliografie tematiche / Biotic communities

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Letteratura scientifica selezionata sul tema "Biotic communities"

Autore: Grafiati
Pubblicato: 4 giugno 2021
Ultima modifica: 30 luglio 2024

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Articoli di riviste sul tema "Biotic communities"

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Bennett, Bradley C., S. Kawano, J. H. Connell e T. Hidaka. "Evolution and Coadaptation in Biotic Communities." Brittonia 42, n. 1 (gennaio 1990): 11. http://dx.doi.org/10.2307/2807020.

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Permogorskiy, M. S. "Competitive intransitivity among species in biotic communities". Biology Bulletin Reviews 5, n. 3 (maggio 2015): 213–19. http://dx.doi.org/10.1134/s2079086415030068.

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Wang, Yonghui, Xiaxia Niu, Liqing Zhao, Cunzhu Liang, Bailing Miao, Qing Zhang, Jinghui Zhang, Bernhard Schmid e Wenhong Ma. "Biotic stability mechanisms in Inner Mongolian grassland". Proceedings of the Royal Society B: Biological Sciences 287, n. 1928 (3 giugno 2020): 20200675. http://dx.doi.org/10.1098/rspb.2020.0675.

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Abstract (sommario):
Biotic mechanisms associated with species diversity are expected to stabilize communities in theoretical and experimental studies but may be difficult to detect in natural communities exposed to large environmental variation. We investigated biotic stability mechanisms in a multi-site study across Inner Mongolian grassland characterized by large spatial variations in species richness and composition and temporal fluctuations in precipitation. We used a new additive-partitioning method to separate species synchrony and population dynamics within communities into different species-abundance groups. Community stability was independent of species richness but was regulated by species synchrony and population dynamics, especially of abundant species. Precipitation fluctuations synchronized population dynamics within communities, reducing their stability. Our results indicate generality of biotic stability mechanisms in natural ecosystems and suggest that for accurate predictions of community stability in changing environments uneven species composition should be considered by partitioning stabilizing mechanisms into different species-abundance groups.
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Warwick, R., M. J. S. Tevesz e P. L. McCall. "Biotic Interactions in Recent and Fossil Benthic Communities." Journal of Applied Ecology 22, n. 1 (aprile 1985): 293. http://dx.doi.org/10.2307/2403353.

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Broughton, Jack M., Brian F. Codding, J. Tyler Faith, Kathryn A. Mohlenhoff, Ruth Gruhn, Joan Brenner-Coltrain e Isaac A. Hart. "El Niño frequency threshold controls coastal biotic communities". Science 377, n. 6611 (9 settembre 2022): 1202–5. http://dx.doi.org/10.1126/science.abm1033.

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El Niño has profound influences on ecosystem dynamics. However, we know little about how it shapes vertebrate faunal community composition over centennial time scales, and this limits our ability to forecast change under projections of future El Niño events. On the basis of correlations between geological records of past El Niño frequency and the species composition of bird and fish remains from a Baja California bone deposit that spans the past 12,000 years, we documented marked faunal restructuring when major El Niño events occurred more than five times per century. This tipping point has implications for the past and future ecology of eastern Pacific coastal environments.
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Schmid, Rudolf, David E. Brown e Charles H. Lowe. "Biotic Communities: Southwestern United States and Northwestern Mexico". Taxon 44, n. 4 (novembre 1995): 659. http://dx.doi.org/10.2307/1223522.

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Fraser, Danielle, e S. Kathleen Lyons. "Biotic interchange has structured Western Hemisphere mammal communities". Global Ecology and Biogeography 26, n. 12 (16 novembre 2017): 1408–22. http://dx.doi.org/10.1111/geb.12667.

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Hagberg, Jacob, Niclas Jonzén, Per Lundberg e Jörgen Ripa. "Uncertain biotic and abiotic interactions in benthic communities". Oikos 100, n. 2 (febbraio 2003): 353–61. http://dx.doi.org/10.1034/j.1600-0706.2003.12138.x.

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Semenchenko, Vitaliy P., Vladimir I. Razlutskij, Irina Yu Feniova e Denis N. Aibulatov. "Biotic relations affecting species structure in zooplankton communities". Hydrobiologia 579, n. 1 (12 dicembre 2006): 219–31. http://dx.doi.org/10.1007/s10750-006-0411-x.

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Tóth, Anikó B., S. Kathleen Lyons, W. Andrew Barr, Anna K. Behrensmeyer, Jessica L. Blois, René Bobe, Matt Davis et al. "Reorganization of surviving mammal communities after the end-Pleistocene megafaunal extinction". Science 365, n. 6459 (19 settembre 2019): 1305–8. http://dx.doi.org/10.1126/science.aaw1605.

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Abstract (sommario):
Large mammals are at high risk of extinction globally. To understand the consequences of their demise for community assembly, we tracked community structure through the end-Pleistocene megafaunal extinction in North America. We decomposed the effects of biotic and abiotic factors by analyzing co-occurrence within the mutual ranges of species pairs. Although shifting climate drove an increase in niche overlap, co-occurrence decreased, signaling shifts in biotic interactions. Furthermore, the effect of abiotic factors on co-occurrence remained constant over time while the effect of biotic factors decreased. Biotic factors apparently played a key role in continental-scale community assembly before the extinctions. Specifically, large mammals likely promoted co-occurrence in the Pleistocene, and their loss contributed to the modern assembly pattern in which co-occurrence frequently falls below random expectations.
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Tesi sul tema "Biotic communities"

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Henriksson, Anna. "Biotic resistance in freshwater fish communities". Doctoral thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-110251.

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Invasions of non-native species cause problems in ecosystems worldwide, and despite the extensive effort that has been put into research about invasions, we still lack a good understanding for why some, but not other, communities resist these invasions. In this doctoral thesis I test hypotheses on biotic resistance using a large dataset of more than 1000 both failed and successful introductions of freshwater fish into Swedish lakes. We have found that the classic species richness hypothesis is a poor descriptor of introduction success because it fails to acknowledge that resident species contribute to the resistance in different ways. We developed a new measure of biotic resistance, the weighted species richness, which takes into account that the resident species contributes to the resistance with different strength and sign. Further, we correlated performance traits of species in their role as an invader and as a resident species to predict how the biotic resistance of these communities would develop over time. We found a positive correlation between performance traits: Some species have high introduction success, they make a large contribution to the resistance, and they cause extinctions when introduced but do not go extinct themselves when other species establishes, whereas other species are weak performers in these respects. Thus, the biotic resistance of these communities should grow stronger as non-native species accumulates. These results give us clues about what type of communities that should be most sensitive to further invasions, i.e., communities harboring species weak performers.  My results show that the biotic resistance of communities is an important factor in determining invasibility of a community. They also show that methods for quantifying resistance must take into account how interactions are structured in nature. What determine the biotic resistance of a community is the type of interactions that the resident species have with the invader and not the species richness of the community.
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Ricks, Kevin Daniel. "Biotic Filtering in Endophytic Fungal Communities". BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/6871.

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Plants can be colonized by complex communities of endophytic fungi. This thesis presents two studies, both of which investigate biotic filtering in endophytic fungal communities. Chapter 1. Endophytic fungi can be acquired horizontally via propagules produced in the environment such as in plant litters of various species. Given that litters from different plant species harbor distinct endophytic fungal communities and that endophytic fungi may be dispersal-limited, the structure of the endophytic fungal community of a given plant may be determined by proximity to particular inoculum sources. Community assembly may also be affected by biotic filtering by the plant. Therefore, a plant may be able to select particular fungal taxa from among the available pool. In that case, the structure of the endophytic fungal community in the plant could be somewhat independent of the structure of the inoculum community. We tested the hypothesis that biotic filtering of endophytic fungal communities occurs in Bromus tectorum by exposing it to a variety of inoculum sources including litters from several co-occurring plant species. The inoculum sources differed significantly from each other in the structures of the communities of endophytic fungi they harbored. We characterized the structures of the resulting leaf and root endophytic fungal communities in Bromus tectorum using high-throughput sequencing. All tested inoculum sources successfully produced complex communities of endophytic fungi in Bromus tectorum. There was significantly more variation in the structures of the communities of endophytic fungi among the inoculum sources than in the resultant endophytic fungal communities in the leaves and roots of Bromus tectorum. These results suggest that biotic filtering by Bromus tectorum played a significant role in the assembly of the endophytic fungal communities in tissues of Bromus tectorum. Because endophytic fungi influence plant fitness, it is reasonable to expect there to be selective pressure to develop a uniform, desirable endophytic fungal community even from disparate inoculum sources via a process known as biotic filtering. Chapter 2. Frequently one finds that different plant species harbor communities that are distinct. However, the nature of this interspecific variation is not clear. We characterized the endophytic fungal communities in six plant species from the eastern Great Basin in central Utah. Four of the species are arbuscular mycorrhizal (two in the Poaceae and two in the Asteraceae), while the other two species are nonmycorrhizal (one in the Brassicaceae and one in the Amaranthaceae). Our evidence suggests that both host mycorrhizal status and phylogenic relatedness independently influence endophytic fungal community structure.
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MacDonald, Arthur Andrew Meahan. "Abiotic and biotic factors creating variation among bromeliad communities". Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/58954.

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Many ecological communities show variation from place to place; understanding the causes of this variation is the goal of community ecology. Differences in community composition will be the result of both stochastic and deterministic processes. However, it is difficult to know to what degree deterministic processes will shape community composition. In this thesis I combined observational and experimental approaches to quantify deterministic processes within a particular ecological community -- they phytotelmata of bromeliad plants. In my thesis I describe three studies at different scales of organization: 1) do organisms of different size respond equally to changes in their environment 2) how do predators interact to influence prey survival 3) what mechanisms underly the response of similar species to the same environmental gradient, bromeliad size. In Chapter 1, I tested an hypothesis developed from previous observational data -- that smaller organisms respond less than larger ones to the same environmental gradient -- different bromeliad species that occur under different forest canopies. After removing variation caused by dispersal, I found that environmental variation explained little variation for bacteria, more for zooplankton and most of all for macroinvertebrates. In my second chapter, I examined ecological determinism on a smaller scale -- within a single trophic level (macroinvertebrate predators). I found that predators may interfere with each other, reducing predation rates and increasing prey survival. In Chapter 3, I examine macroinvertebrate responses to bromeliad volume. I use both null models and a field experiment to show that for at least one such pair, a difference in abiotic tolerances may be the plausible mechanism. Together these results illustrate when, and to what degree, bromeliad communities respond to deterministic factors. All three chapters first demonstrate a pattern, testing it against a suitable null distribution, before attempting to quantify possible mechanisms with a field experiment. This combination of observation and experiment is an approach which can contribute to our understanding of how ecological systems work.
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Theron, Leon-Jacques. "Distribution and abundance of rodents, millipedes and trees in coastal dune forests in northern KwaZulu-Natal". Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/03292006-103859.

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Waterhouse, Martin. "On the edge : peripheral communities and marginal anthropology". Thesis, University of South Wales, 2002. https://pure.southwales.ac.uk/en/studentthesis/on-the-edgeperipheral-communities-and-marginal-anthropology(ef955531-baf0-445a-9e41-6720a9874a88).html.

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This is a study of people, place, and cultural "identity" in two small parishes that are geographically on the periphery of the United Kingdom. Both are coastal parishes: one is in South-west Wales overlooking the Irish Sea and the other is one of the islands comprising The Orkney archipelago.' This is also a work of marginal anthropology (Fox, 1975) that discusses both conventional and more experimental "ways of telling" in an attempt to interpret human social behaviour.
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Karsten, Jennifer. "Teaching about complexity in primary and secondary schools : an exploration of new approaches to ecosystem education". Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=85174.

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The purpose of this research was to investigate ways in which complexity could be used as the paradigm through which schoolchildren might understand ecosystems in a new way. To that end, new conceptual and practical approaches for learning about ecosystems have been presented, and the effects of these approaches on teachers and other educational stakeholders have been explored. A variety of learning environments were visited and over two hundred educational stakeholders were consulted. This resulted in a number of suggestions on and a discussion of the introduction of complexity, as a lens by which to teach about ecosystems and as a teachable subject, within that context, to pre-university schoolchildren.
The development of the learning and teaching approaches for this age group (primary and secondary school) involved exploring the state of ecosystem studies as they are presently conducted, and seeking the content within the current curricula that had congruity with the content of interest: ecosystem phenomena related to complexity. The insights gained from that investigation led to the creation of two types of approach, an approach to learning about ecosystems through the lens of complexity, and an approach to teaching about ecosystems through the lens of complexity. The Complexity Conceptual Approach deals with the various ways of understanding, or conceptualizing, ecosystem complexity and the Complexity Practical Approach deals with the content, technology, and methodology used for instruction on ecosystem complexity. The two approaches can be used together as part of a "complexity framework" that is flexible enough to be used in a diverse variety of learning situations.
Substantial consideration was given to the foreseeable prospects for these approaches: how implementation might occur, the issues involved, and the anticipated outcomes. Accordingly, topics of discussion include the introduction of the conceptual and practical approaches in terms of their effects on various educational stakeholders (such as teachers, students, parents, and administrators) and on different levels of the educational system. This type of investigation (in which potential impacts are considered) is, itself, reflective of the kind of systems-thinking that the complexity approaches were established to engender in schoolchildren.
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Fultz, Jessica Erin. "Effects of shelterwood management on flower-visiting insects and their floral resources". Thesis, Montana State University, 2005. http://etd.lib.montana.edu/etd/2005/fultz/FultzJ0805.pdf.

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Shanmuganathan, Subana. "Soft systems analysis of ecosystems thesis submitted to Auckland University of Technology in fulfillment of the degree of Doctor of Philosophy, 2004". Full thesis. Abstract, 2004.

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Boller, Michael Louis. "Hydrodynamics of marine macroalgae : biotic and physical determinants of drag /". View online ; access limited to URI, 2005. http://0-wwwlib.umi.com.helin.uri.edu/dissertations/dlnow/3188836.

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Jaeger, Andrea L. "Invasive species impacts on ecosystem structure and function". Diss., Connect to online resource - MSU authorized users, 2006.

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Libri sul tema "Biotic communities"

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Martin, Norman Duncan. Biotic forest communities of Ontario. 3a ed. Belleville, Ont: Commonwealth Research, 2001.

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1936-, Kawano Shōichi, Connell Joseph H e Hidaka Toshitaka 1930-, a cura di. Evolution and coadaptation in biotic communities. [Tokyo]: University of Tokyo Press, 1987.

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1955-, Reichenbacher Frank, e Franson Susan E. 1953-, a cura di. A classification of North American biotic communities. Salt Lake City: University of Utah Press, 1998.

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Theberge, John B. Keele Peak resource survey: Biotic aspects. Waterloo, Ont: President's Committee on Northern Studies, University of Waterloo, 1986.

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Bastedo, Jamie. Aishihik Lake resource survey: Biotic aspects. Waterloo, Ont: President's Committee on Northern Studies, University of Waterloo, 1986.

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Theberge, John B. Kluane North resource survey: Biotic aspects. Waterloo, Ont: President's Committee on Northern Studies, University of Waterloo, 1986.

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Keller, David R. Ecology and Justice—Citizenship in Biotic Communities. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-11636-1.

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Martin, Norman Duncan. Handbook of biotic forest communities of Ontario. 2a ed. Belleville, Ont: Commonwealth Research, 1994.

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Paul, Nelson. The terrestrial natural communities of Missouri. Jefferson City, Mo: Missouri Dept. of Natural Resources, 1985.

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Reschke, Carol. Ecological communities of New York state. Latham, NY (700 Troy-Schenectady Rd., Latham 12110-2400): New York Natural Heritage Program, N.Y.S. Dept. of Environmental Conservation, 1990.

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Capitoli di libri sul tema "Biotic communities"

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Griffiths, Mel, e Lynnell Rubright. "Biotic Communities". In Colorado, 61–81. 1. Colorado—Description and travel—1981- . I. Rubright, Lynnell. II. Title. III. Series. F781.3.G74 1983 978.8 83-10180: Routledge, 2019. http://dx.doi.org/10.4324/9780429049422-4.

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Heckman, Charles W. "Biotic communities". In Monographiae Biologicae, 388–417. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-017-3423-3_9.

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Spellerberg, Ian F. "Ecological evaluation of biotic communities". In Evaluation and Assessment for Conservation, 113–69. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-011-2302-0_5.

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van de Koppel, Johan, Jelte van Andel e Arjen Biere. "Ecology of Ecosystems and Biotic Communities". In Restoration Ecology, 59–72. Chichester, UK: John Wiley & Sons, Ltd, 2012. http://dx.doi.org/10.1002/9781118223130.ch6.

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Wootton, R. J. "Biotic Factors and the Structure of Fish Communities". In Fish Ecology, 59–76. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-011-3832-1_3.

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Callaway, Ragan M., e Jacob E. Lucero. "Soil biota and non-native plant invasions." In Plant invasions: the role of biotic interactions, 45–66. Wallingford: CABI, 2020. http://dx.doi.org/10.1079/9781789242171.0045.

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Abstract The trajectory of plant invasions - for better or for worse - can be tied to interactions between plants and the soil community. Here, we highlight five broad ways in which belowground interactions can influence the trajectory of biological invasions by non-native plant species. First, many non-native plant species in their non-native ranges can interact very differently with the resident soil community than do native species. Second, non-native plant species often interact very differently with the soil community in their non-native ranges than in their native ranges, which can result in enemy release from antagonistic interactions. Third, non-native plant species can cultivate a soil community that disproportionately harms native competitors in invaded communities. Fourth, antagonistic soil biota in invaded communities can reduce the performance of non-native plant species, resulting in meaningful biotic resistance against invasion. Fifth, besides or in addition to antagonistic interactions with soil biota, soil mutualisms can promote the success of invasive plant species (i) when mutualists co-invade with non-native plant species that require obligate specialist mutualists, (ii) when mutualists enhance the performance of non-native plant species in their non-native ranges, and (iii) when biotic interactions in the invaded community suppress the soil mutualists of native plant species. We conclude that management practices aimed at manipulating plant - soil interactions have considerable potential to help control plant invasions, but further work is needed to understand the spatial, temporal, taxonomic and biogeographic drivers of context dependence in interactions among plants and soil biota.
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Kaiser-Bunbury, Christopher N., e Benno I. Simmons. "Restoration of pollination interactions in communities invaded by non-native plants." In Plant invasions: the role of biotic interactions, 377–90. Wallingford: CABI, 2020. http://dx.doi.org/10.1079/9781789242171.0377.

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Abstract Invasive plant species degrade and homogenize ecosystems worldwide, thereby altering ecosystem processes and function. To mitigate and reverse the impact of invasive plants on pollination, a key ecosystem function, conservation scientists and practitioners restore ecological communities and study the impact of such management interventions on plant-pollinator communities. Here, we describe opportunities and challenges associated with restoring pollination interactions as part of a holistic ecosystem-based restoration approach. We introduce a few general concepts in restoration ecology, and outline best planning and evaluation practices of restoring pollination interactions on the community level. Planning involves the selection of suitable plant species to support diverse pollinator communities, which includes considerations of the benefits and disadvantages of using native vs exotic, and bridge and framework plant species for restoration. We emphasize the central role of scientific- and community-level approaches for the planning phase of pollination restoration. For evaluation purposes, we argue that appropriate network indicators have the advantage of detecting changes in species behaviour with consequences for ecosystem processes and functions before these changes show up in altered species communities. Suitable network metrics may include interaction diversity and evenness, and network measures that describe the distribution of species, such as network and species-level specialization, modularity and motifs. Finally, we discuss the usefulness of the network approach in evaluating the benefits of restoration interventions for pollination interactions, and propose that applied network ecologists take a central role in transferring theory into practice.
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da Silva, Fernanda Ribeiro, e Marco Aurélio Pizo. "Restoration of seed dispersal interactions in communities invaded by non-native plants." In Plant invasions: the role of biotic interactions, 391–401. Wallingford: CABI, 2020. http://dx.doi.org/10.1079/9781789242171.0391.

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Abstract Restoration aims to rebuild not only species but also the tangled interactions between species that ensure communities perpetuate by themselves. In tropical forests, restoration of seed dispersal interactions is essential because most plant species depend on animals to spread their seeds. A big challenge in restoring such forests is dealing with invasion by non-native species. Non-native plant species may outcompete and eliminate native species from the community, potentially disrupting or arresting the restoration process. Once established, invasive non-native plants are usually incorporated into the local seed dispersal network, potentially causing loss of biodiversity by competition with native species. This chapter reports on a case study of a 25-year old restored forest invaded by several bird-dispersed plant species. We assessed network metrics at the species level to specifically evaluate the role performed by invasive non-native species in the structure of the bird - seed dispersal network. The removal of invasive non-native plants and the re-establishment of native plant communities should be considered for the restoration of habitats invaded by non-native plants. For this reason, we discuss the impacts of removing such non-native plants and explore the consequences for the structure of the overall network. Because restoration areas are open systems, even after the removal of invasive non-native plant species they can return via seed dispersal. So, both the control and management of invasive non-native species would be more effective if planned with a landscape perspective. We also point out relevant management aspects to avoid the negative influence of invasive non-native plants on the seed dispersal interactions occurring between native plant and bird species in restored tropical forests.
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Traveset, Anna, e David M. Richardson. "Plant invasions: the role of biotic interactions - an overview." In Plant invasions: the role of biotic interactions, 1–25. Wallingford: CABI, 2020. http://dx.doi.org/10.1079/9781789242171.0001.

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Abstract Diverse biotic interactions between non-native plant species and other species from all taxonomic groups are crucial mediators of the dynamics of plant invasions. This chapter reviews the key hypotheses in invasion ecology that invoke biotic interactions to explain aspects of plant invasion dynamics. We examine the historical context of these hypotheses and assess the evidence for accepting or rejecting their predictions. Most hypotheses invoke antagonistic interactions, mainly competition, predation, herbivory interactions and the role of pathogens. Only in the last two decades have positive (facilitative/mutualistic) interactions been explicitly included in invasion biology theory (as in ecological theory in general). Much information has accumulated in testing hypotheses relating to biotic resistance and Enemy Release Theory, although many of the emerging generalizations are still contentious. There is growing consensus that other drivers of plant invasion success, such as propagule pressure and disturbance, mediate the outcome of biotic interactions, thereby complicating our ability to make predictions, but these have rarely been assessed in both native and adventive ranges of non-native invasive species. It is also widely acknowledged that biogeographic comparisons, more than common garden experiments, are needed to shed light on many of the contradictory results. Contrasting findings have also emerged in exploring the roles of positive interactions. Despite strong evidence that such interactions are crucial in many communities, more work is needed to elucidate the factors that influence the relative importance of positive and negative interactions in different ecosystems. Different types of evidence in support of invasional meltdown have emerged for diverse habitats and across spatial scales. In light of increasing evidence that biotic indirect effects are crucial determinants of the structure, dynamics and evolution of ecological communities, both direct and indirect interactions involving native and non-native species must be considered to determine how they shape plant invasion patterns and the ecological impacts of non-native species on recipient communities. Research that examines both biotic interactions and the factors that mediate their strength and alter interaction outcomes is needed to improve our ability to predict the effects of novel interactions between native and non-native species, and to envisage how existing invaded communities will respond to changing environmental conditions. Many opportunities exist for manipulating biotic interactions as part of integrated control strategies to reduce the extent, density and impacts of non-native plant invasions. These include the introduction of species from the native range of the non-native plant for biological control, diverse manipulations of plant - herbivore interactions and many types of interaction to enhance biotic resistance and steer vegetation recovery following non-native plant control.
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Wandrag, Elizabeth M., e Jane A. Catford. "Competition between native and non-native plants." In Plant invasions: the role of biotic interactions, 281–307. Wallingford: CABI, 2020. http://dx.doi.org/10.1079/9781789242171.0281.

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Abstract The introduction of species to new locations leads to novel competitive interactions between resident native and newly-arriving non-native species. The nature of these competitive interactions can influence the suitability of the environment for the survival, reproduction and spread of non-native plant species, and the impact those species have on native plant communities. Indeed, the large literature on competition among plants reflects its importance in shaping the composition of plant communities, including the invasion success of non-native species. While competition and invasion theory have historically developed in parallel, the increasing recognition of the synergism between the two themes has led to new insights into how non-native plant species invade native plant communities, and the impacts they have on those plant communities. This chapter provides an entry point into the aspects of competition theory that can help explain the success, dominance and impacts of invasive species. It focuses on resource competition, which arises wherever the resources necessary for establishment, survival, reproduction and spread are in limited supply. It highlights key hypotheses developed in invasion biology that relate to ideas of competition, outlines biotic and abiotic factors that influence the strength of competition and species' relative competitive abilities, and describes when and how competition between non-native and native plant species can influence invasion outcomes. Understanding the processes that influence the strength of competition between non-native and native plant species is a necessary step towards understanding the causes and consequences of biological invasions.
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Atti di convegni sul tema "Biotic communities"

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Miljanović, Branko, Ivana Mijić Oljačić, Aleksandar Bajić, Sonja Pogrmić, Nemanja Pankov e Tamara Jurca. "MULTI-YEAR CHANGES IN THE HYDROBIOLOGICAL PARAMETERS OF "TIKVARA" NATURE PARK". In 53rd Annual Conference of the Serbian Water Pollution Control Society. SERBIAN WATER POLLUTION CONTROL SOCIETY, 2024. http://dx.doi.org/10.46793/voda24.111m.

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Lake Tikvara is the most significant hydrological unit of the "Tikvara" Nature Park. The paper presents the results of hydrobiological research with the aim of monitoring the fish fauna and relevant ecological factors of the "Tikvara" hydroecosystem from 2018 to 2023. The association of selected abiotic parameters, including changes in the water level of the Danube, with changes in the structure of the phytoplankton, benthic, and nektonic communities of Tikvara was analyzed. The results indicated the existence of a connection between the period of high and low water levels and the structure of the investigated communities, which was also reflected, indirectly, by the association of changes in biotic communities with the variation of certain abiotic (temperature, transparency) and biotic components (intraspecies relationships) of this unique hydroecosystem
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Marcinkevage, A. Catherine, e E. E. Herricks. "An Individual-Based Model for Evaluating the Effects of Hydrology on Biotic Stream Communities". In World Environmental and Water Resources Congress 2007. Reston, VA: American Society of Civil Engineers, 2007. http://dx.doi.org/10.1061/40927(243)600.

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O'Neil, Gretchen R., James D. Schiffbauer, James D. Schiffbauer, John Warren Huntley, John Warren Huntley, Yaoping Cai e Yaoping Cai. "THE IMPORTANCE OF BIOTIC INTERACTIONS IN SHAPING EDIACARAN BENTHIC COMMUNITIES: A COMPARATIVE CASE STUDY OF THE GAOJIASHAN AND MISTAKEN POINT BIOTAS". In GSA Annual Meeting in Denver, Colorado, USA - 2016. Geological Society of America, 2016. http://dx.doi.org/10.1130/abs/2016am-287195.

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Shamala, Mikhail M. "Ecological toponyms of Lutugino District". In The libraries and ecological education: Theory and practice. Russian National Public Library for Science and Technology, 2020. http://dx.doi.org/10.33186/978-5-85638-227-2-2020-300-307.

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The concept of «ecological toponymics» has been developed since 1993. The main tas of the discipline is to investigate into toponymic evidences of physicogeographic conditions and landscapes of the past, ecofactors that influenced demic diffusion and adaptation to new sociogeographic and landscape environment, tracing areas of biotic communities and individual species lost in anthropogenesis. E. L Lyubimova, E. M. Murzaev, V. S. Zhekulin and others were The pioneers of these studies tas.
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CHAND, NIRBHAY. "Impact of Gravel Extraction on Stream Morphology and Biotic Communities in Streams of Vanua Levu Fiji". In Fourth International Conference On Advances in Applied Science and Environmental Engineering - ASEE 2015. Institute of Research Engineers and Doctors, 2015. http://dx.doi.org/10.15224/978-1-63248-068-2-05.

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Kempf, Hannah L., Ashley A. Dineen, Peter D. Roopnarine e Carrie L. Tyler. "USING FOOD WEBS TO EXAMINE ECOSYSTEM DYNAMICS DURING BIOTIC INVASIONS IN LATE ORDOVICIAN SHALLOW MARINE COMMUNITIES". In GSA Annual Meeting in Denver, Colorado, USA - 2016. Geological Society of America, 2016. http://dx.doi.org/10.1130/abs/2016am-283943.

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Rubtsova, Svetlana, Svetlana Rubtsova, Natalya Lyamina, Natalya Lyamina, Aleksey Lyamin e Aleksey Lyamin. "ANALYSIS OF THE FUNCTIONING OF MARINE ECOSYSTEMS ON CHANGING THE PARAMETERS OF THE BIOLUMINESCENCE FIELD ON THE CRIMEAN BLACK SEA SHELF". In Managing risks to coastal regions and communities in a changing world. Academus Publishing, 2017. http://dx.doi.org/10.31519/conferencearticle_5b1b9387ec5c97.58539127.

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Abstract (sommario):
The concept of a new approach to environmental assessment is offered in the system of integrated management of the resource and environmental safety of the coastal area of the Black Sea. The studies of the season and daily changeability in the bioluminescence field in the Sevastopol coastal waters has been conducted. For the first time considerable differences in the bioluminescence field seasonal changes in the surface and deep water layers and the reasons conditioning this phenomenon have been shown, using a method of multidimensional statistical analysis. The bioluminescence field vertical profile change in the Black sea coastal waters in the autumn period at night has been studied. It has been shown that according to the character of bioluminescence parameters dynamics a water column can be divided into layers: upper (0 – 35 m) and deep water (36 – 60 m). It has been revealed that life rhythms of the plankton community are the main reason for the bioluminescence field intensity variability. It has been revealed that 14-hour periodicity of the bioluminescence field is related to the changes in light and its variations with 2,5…4,5 hours are conditioned by planktonts endogenous daily rhythms. And here biotic factors effect mostly periodicity of the bioluminescence field intensity increase and fall down at the dark time of the day. Abiotic factors are of less importance in circadian rhythmic of the bioluminescence field in the neritic zone.
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Rubtsova, Svetlana, Svetlana Rubtsova, Natalya Lyamina, Natalya Lyamina, Aleksey Lyamin e Aleksey Lyamin. "ANALYSIS OF THE FUNCTIONING OF MARINE ECOSYSTEMS ON CHANGING THE PARAMETERS OF THE BIOLUMINESCENCE FIELD ON THE CRIMEAN BLACK SEA SHELF". In Managing risks to coastal regions and communities in a changing world. Academus Publishing, 2017. http://dx.doi.org/10.21610/conferencearticle_58b43168bfc21.

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Abstract (sommario):
The concept of a new approach to environmental assessment is offered in the system of integrated management of the resource and environmental safety of the coastal area of the Black Sea. The studies of the season and daily changeability in the bioluminescence field in the Sevastopol coastal waters has been conducted. For the first time considerable differences in the bioluminescence field seasonal changes in the surface and deep water layers and the reasons conditioning this phenomenon have been shown, using a method of multidimensional statistical analysis. The bioluminescence field vertical profile change in the Black sea coastal waters in the autumn period at night has been studied. It has been shown that according to the character of bioluminescence parameters dynamics a water column can be divided into layers: upper (0 – 35 m) and deep water (36 – 60 m). It has been revealed that life rhythms of the plankton community are the main reason for the bioluminescence field intensity variability. It has been revealed that 14-hour periodicity of the bioluminescence field is related to the changes in light and its variations with 2,5…4,5 hours are conditioned by planktonts endogenous daily rhythms. And here biotic factors effect mostly periodicity of the bioluminescence field intensity increase and fall down at the dark time of the day. Abiotic factors are of less importance in circadian rhythmic of the bioluminescence field in the neritic zone.
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McLoughlin, Stephen, Vivi Vajda, Christopher Mays, Christopher R. Fielding, Tracy D. Frank e Robert S. Nicoll. "EXTINCTION AND RECOVERY OF GONDWANAN PLANT AND HERBIVOROUS ARTHROPOD COMMUNITIES THROUGH THE PERMIAN-TRIASSIC BIOTIC CRISIS IN SOUTHERN HIGH PALAEOLATITUDES". In GSA Annual Meeting in Indianapolis, Indiana, USA - 2018. Geological Society of America, 2018. http://dx.doi.org/10.1130/abs/2018am-318786.

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Adegoke, Samuel Oluwafikayo, Olugbenga Adebanjo Falode e Princess Christiana Nwankwo. "Understanding Oilfield Scale Deposition and Inhibition Mechanisms for Optimum Management: A Review". In SPE Nigeria Annual International Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/207133-ms.

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Abstract (sommario):
Abstract Oilfield scales are crystalline minerals made up of Na, K, Mg, Ca, Ba, Sr, Fe, Cl from produced water that can precipitate out in the reservoir, well, pipelines and process during the production and transportation of oil and gas. These precipitates can deposit as a result of thermodynamic and/or chemical changes and pose costly flow assurance issues to the oil industry. Several factors have been identified to be responsible including temperature, pressure, ionic strength, pH, evaporation, bicarbonate anion, super-saturation and contact time and water chemistry. Attempts to solve this problem in the past have focused mainly on the use of chemical inhibitors and the most accepted mechanism of scale inhibition is squeeze injection method. While adsorption and retention of scale inhibitors on rock formations needs more research, there had been improvement to better ways of ensuring adsorption and precipitation through nanotechnology including the use of nano-carbon enhanced squeeze treatment (NCEST). The uses of these conventional inhibitors have been found to be toxic to the flora and fauna in biotic communities during water disposal. In order to reduce the environmental burden caused by these conventional solutions and still manage the problem effectively, greener solutions have been proposed. This review x-rays the mechanisms of scale precipitation and deposition, evaluate the solutions that have been provided in literature based on efficiency, economics and environmental impact and propose guidelines to field operators in selecting optimum solutions.
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Rapporti di organizzazioni sul tema "Biotic communities"

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Dodd, Hope, J. Cribbs, David Bowles, Cameron Cheri e Jeffrey Williams. Aquatic community monitoring at Effigy Mounds National Monument, 2008?2017. National Park Service, 2023. http://dx.doi.org/10.36967/2300634.

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Abstract (sommario):
Dousman Creek, located in northeastern Iowa, is a Class ?B? coldwater stream that supports a trout population and is listed among the Outstanding Iowa Waters (Iowa Department of Natural Resources 2010, 2016). The Heartland Inventory and Monitoring Network (Heartland Network) of the National Park Service (NPS) has been monitoring aquatic communities (fish and invertebrates) in Dousman Creek within Effigy Mounds National Monument (NM) since 2008. Corresponding physical habitat and water quality were also collected during biotic sampling. The objectives of this long-term monitoring program are to assess the status and trends in the biotic stream community and relate these trends to environmental variables. The purpose of this report is to summarize the baseline aquatic community data collected during three sampling events conducted from 2008 to 2017. The fish community was dominated by the intolerant cool/cold-water species Brown trout (Salmo trutta) and Mottled sculpin (Cottus bairdii) in 2008, while more tolerant white sucker (Catostomus comersonii) and Johnny darter (Etheostoma nigrum) were most abundant in 2014. During 2017, fish community composition was more evenly distributed among species present. Benthic invertebrate samples were dominated by the moderately intolerant mayfly genus Pseudocloeon and blackfly genus Simulium in 2008 and 2014, while the invertebrate samples in 2017 were dominated primarily by a tolerant, mayfly taxa (Baetis) and Oligochaetes. The abundance of aquatic invertebrates in 2017 was more than ten times lower than invertebrate abundance in 2008 and 2014. Water quality data collected by the Heartland Network did not indicate any of the five parameters (temperature, dissolved oxygen, pH, specific conductance, or turbidity) exceeded the Iowa Department of Natural Resources water quality standards, however the number of hourly measurements were low (4?20 measurements) depending on year sampled. Three years of data are currently insufficient to fully characterize the stream integrity of Dousman Creek based on fish and invertebrate communities. Continued long-term monitoring of Dousman Creek will allow for better assessment of the biotic integrity and overall quality of the stream.
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Dodd, Hope, David Peitz, Gareth Rowell, Janice Hinsey, David Bowles, Lloyd Morrison, Michael DeBacker, Jennifer Haack-Gaynor e Jefrey Williams. Protocol for Monitoring Fish Communities in Small Streams in the Heartland Inventory and Monitoring Network. National Park Service, aprile 2021. http://dx.doi.org/10.36967/nrr-2284726.

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Abstract (sommario):
Fish communities are an important component of aquatic systems and are good bioindicators of ecosystem health. Land use changes in the Midwest have caused sedimentation, erosion, and nutrient loading that degrades and fragments habitat and impairs water quality. Because most small wadeable streams in the Heartland Inventory and Monitoring Network (HTLN) have a relatively small area of their watersheds located within park boundaries, these streams are at risk of degradation due to adjacent land use practices and other anthropogenic disturbances. Shifts in the physical and chemical properties of aquatic systems have a dramatic effect on the biotic community. The federally endangered Topeka shiner (Notropis topeka) and other native fishes have declined in population size due to habitat degradation and fragmentation in Midwest streams. By protecting portions of streams on publicly owned lands, national parks may offer refuges for threatened or endangered species and species of conservation concern, as well as other native species. This protocol describes the background, history, justification, methodology, data analysis and data management for long-term fish community monitoring of wadeable streams within nine HTLN parks: Effigy Mounds National Monument (EFMO), George Washington Carver National Monument (GWCA), Herbert Hoover National Historic Site (HEHO), Homestead National Monument of America (HOME), Hot Springs National Park (HOSP), Pea Ridge National Military Park (PERI), Pipestone National Monument (PIPE), Tallgrass Prairie National Preserve (TAPR), and Wilson's Creek national Battlefield (WICR). The objectives of this protocol are to determine the status and long-term trends in fish richness, diversity, abundance, and community composition in small wadeable streams within these nine parks and correlate the long-term community data to overall water quality and habitat condition (DeBacker et al. 2005).
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Dodd, Hope, David Bowles, John Cribbs, Jeffrey Williams, Cameron Cheri e Tani Hubbard. Aquatic community monitoring at Herbert Hoover National Historic Site, 2008?2017. National Park Service, 2024. http://dx.doi.org/10.36967/2303263.

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Abstract (sommario):
Land use changes that degrade water quality and stream habitat can negatively impact aquatic communities. Monitoring trends in aquatic community composition and habitat conditions is a robust way to assess stream integrity and health. Herbert Hoover National Historic Site (NHS) is in eastern Iowa where dominant land use consists of row-crop and grassland agriculture. A portion of an unnamed tributary of the West Branch of Wapsinonoc Creek, known as Hoover Creek, flows through the park. In 2008, the Heartland Inventory and Monitoring Network (Heartland Network) of the National Park Service (NPS) began monitoring aquatic communities (fish and invertebrates), physical habitat, and water quality at Hoover Creek within the park. This report summarizes four years of data to assess the baseline conditions of Hoover Creek within Herbert Hoover NHS. Aquatic invertebrate taxa richness ranged from 21 to 32 among all years monitored. Three of these taxa are sensitive to poor water quality and habitat conditions. The invertebrate community was dominated by true flies in the Chironomidae family, Oligochaete worms, and mayflies in the Baetidae family. These taxa are all tolerant of poor water quality and habitat conditions. However, in 2011, the sensitive caddisfly Ceratopsyche was also abundant. Mean Hilsenhoff Biotic Index values indicated the invertebrate community fluctuated over time, ranging from fairly poor in 2017 to good condition in 2011. Ten fish species were collected at Hoover Creek across the four years sampled with seven of those species found in all years. All fish species collected were either moderately tolerant or tolerant to poor habitat and water quality conditions; the community was dominated by johnny darter (Etheostoma nigrum), creek chub (Semotilus atromaculatus), and blacknose dace (Rhinichthys atratulus). Based on the Index of Biotic Integrity developed for Iowa streams, the fish community ranged from fair condition in 2008, 2014, and 2017 to good condition in 2011. Hoover Creek was found to have predominately fine to medium gravel substrate with high embeddedness, and banks were steep and tall and consisted of fine silt substrate. With the exception of turbidity after a rain event in 2008, water quality parameters were within state standards. The four years of stream biota data coupled with habitat data should form a good baseline for assessing changes or trends in the aquatic community and overall stream health of Hoover Creek.
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DeSaix, Matthew. Bird community monitoring at New River Gorge National River, Gauley River National Recreation Area, and Bluestone National Scenic River, 1997 - 2018. National Park Service, gennaio 2022. http://dx.doi.org/10.36967/nrr-2289846.

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Abstract (sommario):
Birds are prominent features of National Park Service lands and are effective indicators for monitoring ecosystem health. Assessing the temporal change of avian species abundance depends on long-term monitoring of bird communities and trends, however long-term monitoring programs are generally uncommon. In this report, we summarize 22 years (1997-2018) of point count data across five sites on West Virginia National Park Service lands (three in New River Gorge National River, one in Gauley River National Recreation Area, and one in Bluestone National Scenic River) and compare these results to our analysis of Breeding Bird Survey data for the same time period across all of West Virginia. The objectives of this analysis are two-fold: 1) describe the biotic integrity of the National Park Service lands in West Virginia and 2) Quantify trends in guilds and species abundance. During the 20-year period of this survey, 85 breeding resident species were detected. The West Virginia National Park Service lands are home to stable populations of Wood Thrush and Yellow-billed Cuckoo, both species of continental concern by Partners in Flight. Seven species have declined precipitously on NPS lands during this time period. Three of these species are also experiencing declines across the rest of West Virginia (Blue-gray Gnatcatcher, Carolina Chickadee, Kentucky Warbler), but the other 4 species are stable across West Virginia (Acadian Flycatcher, Black-throated Green Warbler, Northern Parula, Swainson’s Warbler). Four species that are declining across West Virginia (Great Crested Flycatcher, Indigo Bunting, Red-eyed Vireo, and Worm-eating Warbler) are stable on southern West Virginia NPS lands. Additionally, the upper-canopy foraging guild of species has decreased significantly on NPS lands in southern West Virginia. An analysis of community biotic integrity revealed that the southern West Virginia NPS lands have been stable at a rating of high biotic integrity every year for the duration of this survey. Future research should delve into the underlying factors that may be driving the trends in abundance at different scales.
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Tsybekmitova, G. Ts, L. D. Radnaeva, N. A. Tashlykova, V. G. Shiretorova, A. K. Tulokhonov, B. B. Bazarova e M. O. Matveeva. THE EFFECT OF CLIMATIC SHIFTS ON BIODIVERSITY OF PHYTOCENOSIS: LAKE ARAKHLEY (EASTERN SIBERIA, RUSSIA). DOICODE, 2020. http://dx.doi.org/10.18411/0973-7308-2020-35-3-77-90.

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Lake Arakhley is located within the Lake Baikal basin in Eastern Siberia, Russia. The area is characterized by continental subarctic climate with considerate diurnal temperature range, long cold dry winters and short hot summers with more precipitation occurring during the latter half of the summer. Climatic shifts in high water years and low water years result in morphometric changes in the lake and in the chemical and physical parameters of the ecosystem. During low water years, concentrations of ammonium nitrogen and nitrite nitrogen are decreased, whereas nitrate concentration increases. High water years feature average concentrations of ammonium ions 1.5–2 times higher than the values of recent dry years. Redundancy analysis (RDA) of abiotic factors and biotic community indicated that the community structure shows the greatest correlation with physical and chemical parameters of water and biogenic elements (nitrites, ammonium, phosphates) along the first axis, and with the lake depth and transparency along the second axis. Changes in abiotic factors induce functioning and formation of characteristic communities of the primary producers in the trophic structure of the ecosystem. During low water years, with increased level of autochthonous organic matter, Lindavia comta dominance is observed, while during high water years, with increased allochthonous organic matter Asterionella formosa appeared as dominant. Currently, during low water years, the hydrophytes community is monodominant and composed of Ceratophyllum demersum. Meanwhile, such species indicating eutrophic conditions as Myriophyllum sibiricum, Potamogeton pectinatus are found in the lake vegetation.
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Lundgren, Jonathan, Moshe Coll e James Harwood. Biological control of cereal aphids in wheat: Implications of alternative foods and intraguild predation. United States Department of Agriculture, ottobre 2014. http://dx.doi.org/10.32747/2014.7699858.bard.

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Abstract (sommario):
The overall objective of this proposal is to understand how realistic strategies for incorporating alternative foods into wheat fields affect the intraguild (IG) interactions of omnivorous and carnivorous predators and their efficacy as biological control agents. Cereal aphids are a primary pest of wheat throughout much of the world. Naturally occurring predator communities consume large quantities of cereal aphids in wheat, and are partitioned into aphid specialists and omnivores. Within wheat fields, the relative abilities of omnivorous and carnivorous predators to reduce cereal aphids depend heavily on the availability, distribution and type of alternative foods (alternative prey, sugar, and pollen), and on the intensity and direction of IG predation events within this community. A series of eight synergistic experiments, carefully crafted to accomplish objectives while accounting for regional production practices, will be conducted to explore how cover crops (US, where large fields preclude effective use of field margins) and field margins (IS, where cover crops are not feasible) as sources of alternative foods affect the IG interactions of predators and their efficacy as biological control agents. These objectives are: 1. Determine the mechanisms whereby the availability of alternative prey and plant-provided resources affect pest suppression by omnivorous and carnivorous generalist predators; 2. Characterize the intensity of IGP within generalist predator communities of wheat systems and assess the impact of these interactions on cereal aphid predation; and 3. Evaluate how spatial patterns in the availability of non-prey resources and IGP affect predation on cereal aphids by generalist predator communities. To accomplish these goals, novel tools, including molecular and biochemical gut content analysis and geospatial analysis, will be coupled with traditional techniques used to monitor and manipulate insect populations and predator efficacy. Our approach will manipulate key alternative foods and IG prey to determine how these individual interactions contribute to the ability of predators to suppress cereal aphids within systems where cover crop and field margin management strategies are evaluated in production scale plots. Using these strategies, the proposed project will not only provide cost-effective and realistic solutions for pest management issues faced by IS and US producers, but also will provide a better understanding of how spatial dispersion, IG predation, and the availability of alternative foods contribute to biological control by omnivores and carnivores within agroecosystems. By reducing the reliance of wheat producers on insecticides, this proposal will address the BARD priorities of increasing the efficiency of agricultural production and protecting plants against biotic sources of stress in an environmentally friendly and sustainable manner.
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Gottlieb, Yuval, Bradley Mullens e Richard Stouthamer. investigation of the role of bacterial symbionts in regulating the biology and vector competence of Culicoides vectors of animal viruses. United States Department of Agriculture, giugno 2015. http://dx.doi.org/10.32747/2015.7699865.bard.

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Abstract (sommario):
Symbiotic bacteria have been shown to influence host reproduction and defense against biotic and abiotic stressors, and this relates to possible development of a symbiont-based control strategy. This project was based on the hypothesis that symbionts have a significant impact on Culicoides fitness and vector competence for animal viruses. The original objectives in our proposal were: 1. Molecular identification and localization of the newly-discovered symbiotic bacteria within C. imicola and C. schultzei in Israel and C. sonorensis in California. 2. Determination of the prevalence of symbiotic bacteria within different vector Culicoides populations. 3. Documentation of specific symbiont effects on vector reproduction and defense: 3a) test for cytoplasmic incompatibility in Cardinium-infected species; 3b) experimentally evaluate the role of the symbiont on infection or parasitism by key Culicoides natural enemies (iridescent virus and mermithid nematode). 4. Testing the role(s) of the symbionts in possible protection against infection of vector Culicoides by BTV. According to preliminary findings and difficulties in performing experimental procedures performed in other insect symbiosis systems where insect host cultures are easily maintained, we modified the last two objectives as follows: Obj. 3, we tested how symbionts affected general fitness of Israeli Culicoides species, and thoroughly described and evaluated the correlation between American Culicoides and their bacterial communities in the field. We also tried alternative methods to test symbiont-Culicoides interactions and launched studies to characterize low-temperature stress tolerances of the main US vector, which may be related to symbionts. Obj. 4, we tested the correlation between EHDV (instead of BTV) aquisition and Cardinium infection. Culicoides-bornearboviral diseases are emerging or re-emerging worldwide, causing direct and indirect economic losses as well as reduction in animal welfare. One novel strategy to reduce insects’ vectorial capacity is by manipulating specific symbionts to affect vector fitness or performance of the disease agent within. Little was known on the bacterial tenants occupying various Culicoides species, and thus, this project was initiated with the above aims. During this project, we were able to describe the symbiont Cardinium and whole bacterial communities in Israeli and American Culicoides species respectively. We showed that Cardinium infection prevalence is determined by land surface temperature, and this may be important to the larval stage. We also showed no patent significant effect of Cardinium on adult fitness parameters. We showed that the bacterial community in C. sonorensis varies significantly with the host’s developmental stage, but it varies little across multiple wastewater pond environments. This may indicate some specific biological interactions and allowed us to describe a “core microbiome” for C. sonorensis. The final set of analyses that include habitat sample is currently done, in order to separate the more intimately-associated bacteria from those inhabiting the gut contents or cuticle surface (which also could be important). We were also able to carefully study other biological aspects of Culicoides and were able to discriminate two species in C. schultzei group in Israel, and to investigate low temperature tolerances of C. sonorensis that may be related to symbionts. Scientific implications include the establishment of bacterial identification and interactions in Culicoides (our work is cited in other bacteria-Culicoides studies), the development molecular identification of C. schultzei group, and the detailed description of the microbiome of the immature and matched adult stages of C. sonorensis. Agricultural implications include understanding of intrinsic factors that govern Culicoides biology and population regulation, which may be relevant for vector control or reduction in pathogen transmission. Being able to precisely identify Culicoides species is central to understanding Culicoides borne disease epidemiology.
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Bingham, Sonia, e Craig Young. Sentinel wetlands in Cuyahoga Valley National Park: I. Ecological characterization and management insights, 2008–2018. A cura di Tani Hubbard. National Park Service, febbraio 2023. http://dx.doi.org/10.36967/2296885.

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Abstract (sommario):
Sentinel wetlands at Cuyahoga Valley National Park (NP) comprise a set of twenty important management areas and reference sites. These wetlands are monitored more closely than other wetlands in the wetlands monitoring program and are the focus of the volunteer monitoring program for water levels. We used the Ohio Rapid Assessment Method (ORAM) to evaluate habitat in the sentinel wetlands. A total of 37 long-term sample plots have been established within these wetlands to monitor biological condition over time using vegetation as an indicator. Vegetation is intensively surveyed using the Vegetation Index of Biotic Integrity (VIBI), where all plant species within the plot are identified to the lowest taxonomic level possible (genus or species). Sample plots were surveyed twice from 2008 to 2018 and the vegetation data were evaluated using five metrics: VIBI, Floristic Quality Assessment Index (FQAI), percent sensitive plant species, percent invasive graminoids, and species richness. These metrics are discussed for each location. This report also highlights relevant land use histories, common native plant species, and invasive species of concern at each wetland. This is the first report in a two-part series, designed to summarize the results from intensive vegetation surveys completed at sentinel wetlands in 2008–2018. Boston Mills, Virginia Kendall Lake, Stumpy Basin, Columbia, and Beaver Marsh are all in excellent condition at one or more plots. They have unique habitats with some specialized plant species. Fawn Pond is in good condition at most plots and scores very high in comparison to other wetlands within the riverine mainstem hydrogeomorphic class. Metric scores across mitigation wetlands were low. Two of the three wetlands (Brookside and Rockside) are not meeting the benchmarks originally established by the United States Army Corps of Engineers and Ohio Environmental Protection Agency. Krejci is still a young mitigation site and success will be determined over time. Park-supported invasive species control efforts will be crucial for long-term success of these sites and future mitigation/restoration projects. The wetlands monitored because of proposed ecological restoration projects (Pleasant Valley, Stanford, and Fawn Pond) have extensive invasive plant communities. These restoration sites should be re-evaluated for their feasibility and potential success and given an order of prioritization relative to the newer list of restoration sites. Cuyahoga Valley NP has added many new areas to their list of potential wetland restoration sites after these areas were selected, and there may be better opportunities available based on restoration objectives. Restoration goals should be based on the park's desired future conditions, and mitigation goals of outside partners may not always be in line with those. The multiple VIBI plots dispersed throughout the large wetlands at Cuyahoga Valley NP detected and illuminated spatial patterns in condition. Many individual wetlands had a wide range of VIBI scores within their boundaries, sometimes reflecting localized disturbances, past modifications, and management actions. Most often, these large fluctuations in condition were linked to local invasive plant infestations. These infestations appear to be the most obvious and widespread threat to wetland ecosystems within the park, but also the most controllable threat. Some sensitive species are still present in some of the lowest scoring plots, which indicates that invasive plant species control efforts may pay off immediately with a resurgence of native communities. Invasive plant control at rare habitat sites would have large payoffs over time by protecting some of the park's most unique wetlands. Reference wetlands would also be good demonstration sites for park managers to try to maintain exemplary conditions through active management. Through this work, park managers can evaluate the feasibility, effectiveness, and scalability of management practices required to maintain wetland condition.
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Peña, Ignacio, e Micaela Jenik. Deep Tech: The New Wave. Inter-American Development Bank, giugno 2023. http://dx.doi.org/10.18235/0004947.

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Abstract (sommario):
DeepTech startups are companies based on a scientific discovery or meaningful engineering innovation. Deep Tech startups involve significant technological risk and R&D. However, Deep Tech innovation is critical to effectively address humanities grand challenges. DeepTech companies have the potential to catalyze change, establish new industries, and disrupt existing ones. Cutting-edge technologies like AI, solar power, electric vehicles, biotech, advanced manufacturing, and space-based broadband have the potential to pave new paths for economic growth, social equity, and environmental sustainability in the region. Today, with 340 ventured-back DeepTech startups, the DeepTech ecosystem in LAC is valued at USD 8 billion and has much potential to grow. The LAC region has strong advantages such as talent and R&D cost, to further develop and grow the DeepTech ecosystem in LAC. By fostering DeepTech in the region, LAC countries will benefit from the creation of jobs, as well as from potential access to improved basic products and services. Poor and vulnerable communities may greatly benefit from the adoption and creation of new technologies.
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Biomonitoring of fish communities, using the Index of Biotic Integrity (IBI) in Rabbit Creek-Cat Creek Watershed, Summer 1992. Office of Scientific and Technical Information (OSTI), agosto 1993. http://dx.doi.org/10.2172/10183541.

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